Is your feature request related to a problem? Please describe.
I would like to be able to add confounding variables to already registered samples.

Describe the solution you'd like
After registration of a batch, it would be nice to be able to add confounding variables (ex. age, sex, BMI, cell culture medium, etc.) when editing the metadata of the batch.

Describe alternatives you've considered
At the moment the information can only be added as a comment, but it would be better to have it as a separate column. The new columns could be added through the browser editing function or, if not possible, by downloading the metadata as txt and uploading it with the additional columns.

Based on personal discussions with @oquendoM @Shraddha0903 and @FraBarSol we conclude some facts and properties for confounding variables in the application:

• can be categorical or continuous
• are not always available beforehand
• can be provided at any point of the project
• are annotations of samples
• can be associated based on the sample name and sample id
• can be incomplete

In the case of an incomplete annotation of samples, warn the user but not block the annotation process. It might be, that there are missing values and the user is aware of it.

The use case

"As a researcher, I want to annotate samples with confounding variables and their value for samples in a batch."

Requirements

• If at least one sample misses an annotation for a provided confounding variable, warn the user before saving any change
• The user is given the sample id and sample name during annotation
• The user can update existing confounding variables